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Yes, you can use the pressure generated by the sound wave or the energy it transmits. For example zero decibels is $10^{-12}$ W/m$^2$. I suspect the dB scale originated because the preception of volume in human hearing is logarithmic i.e. we perceive each successive doubling as a linear volume increment. The dB scale is also logarithmic and maps well onto ...

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Sound is a pressure wave, alternating deviations of pressure from the equilibrium. So, depending on the medium in which the pressure wave passes, you can get either type of wave (longitudinal or transverse): In gases and liquids, the pressure deviations causes compressions and rarefactions, meaning these are longitudinal waves. In solids, the pressure ...

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Natural frequency depends on the physical properties of a system. Some of the classical examples are masses attached to springs and pendula. For the former class, the basic model is based on Hooke's law, which translates into the differential equation (1D) $$m\ddot x + kx = 0,\qquad m,k > 0$$ where any sort of dissipative effect has been neglected. ...

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Here's a simpler answer. Resonance is really all about the capture of energy into a system and its cyclic flow between potential and kinetic states. In mechanical systems we call these states potential energy and kinetic energy, but in electrical systems, as a another example, between magnetic and electrical fields. It's the rate of this cycling back and ...

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Sound is a longitudinal wave whose amplitude stands for its "loudness". When sounds travels in medium, it attenuates, i.e. becomes less loud, exponentially, with an exponential coefficient, $\alpha$. So what you're actually interested in is the change in $\alpha$ with temperature. For newtonian fluid for example, this coefficient is equal to: \alpha = ...

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There are as many branches of acoustic phonons as there are dimensions of the crystal, but they are not necessarily distinct. These three branches will each have a "speed of sound" associated with it, given by the gradient of the frequency-wavenumber graph at the origin. If these are different, it means that the speed of sound will be different in different ...

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